An interpolator may be used to mix two or more different input signals to provide an output signal. In a transceiver, an interpolator may generate an interpolated clock signal having a desired phase by mixing two or more out-of-phase clock signals. Such an interpolator may be used in conjunction with a tracking loop to extract clock information from a data stream received by the transceiver.
Some interpolators may be controlled to provide an output signal having any one of a linear sequence of phase degrees. For example, an interpolator having thirty-two modes of operation may provide output signals having thirty-two different phase degrees, spaced every 360/32=11.5 degrees. An interpolator exhibiting such linear behavior may be desired in some circumstances. It is currently difficult to efficiently detect non-linear behavior in some types of interpolators.